JSON Minifier

Minify JSON in your browser: strip all whitespace for smaller payloads and env vars. Shows size savings. Free, private, no upload.

JSON inputpaste, type, or drop a file
JSON output
Runs 100% in your browser. Nothing is uploaded, logged, or stored, and there are no ads. Verify it yourself: open your browser's Network tab while you convert and watch that no requests leave this page.

About this tool

Strip every byte of unnecessary whitespace from a JSON document. Minified JSON is what you want for HTTP payloads, environment variables, and anywhere size or single-line formatting matters.

The output is byte-for-byte valid JSON that parses identically to your input. Only whitespace is removed.

Common uses

  • Shrink a JSON payload before embedding it in an environment variable.
  • Produce single-line JSON for log lines or CLI arguments.
  • Reduce fixture file size in a repository.

Automate via API

The same conversion is available as a REST endpoint for scripts, pipelines, and backends:

curl -X POST https://payloadly.com/api/v1/tools/json-minifier \
  -H "Content-Type: text/plain" \
  -H "X-Api-Key: YOUR_API_KEY" \
  --data-binary @input.json

API documentation · Get an API key

JSON notes

JSON (JavaScript Object Notation) is the standard interchange format for web APIs, config files, and log pipelines. It is strict: keys must be double-quoted, trailing commas are invalid, and comments are not allowed.

  • JSON does not support comments; they are stripped or rejected by parsers.
  • Trailing commas after the last element are invalid JSON.
  • Integers beyond 2^53 lose precision in JavaScript-based parsers.

Frequently asked questions

Is my data uploaded to a server?

No. This tool runs entirely in your browser using JavaScript, and there are no ads on the page. Nothing you paste or drop here is uploaded, logged, or stored, and you can verify that yourself: open your browser's developer tools and watch the Network tab while you convert (no requests leave the page), or disconnect from the internet after the page loads and keep working.

Is there a size limit or a fee?

The browser tool is free with no signup and comfortably handles files up to tens of megabytes (limited by your device's memory). For automated or bulk processing inside your own scripts and pipelines, use the paid REST API.

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